As can be seen in AngularJS's source, any $http.post request that returns an HTTP code in the 200-299 range will trigger the success() callback even if the response contains invalid data (like for example invalid JSON).
I'm specifically setting my call's responseType: 'json' and even then the success callback is fired when something else comes back. This is especially annoying in the development server where PHP's display_errors setting is turned on. When something goes wrong server-side and PHP outputs an error message the AngularJS app doesn't detect this and continues happily.
Is there a way to prevent this? I mean, to make the AngularJS app fire the error() callback when the response data is invalid JSON?
Thanks
so your PHP server responds with a 200 error code even on an error? Not knowing PHP, this feels like a server configuration problem to me. I'd expect a 500 error with a payload. That being said, there are two things that I can think of offhand.
$http includes transformResponse handlers you can set up to inspect the response for problems.
$http also includes the concept of "interceptors" which allow you to pick up the response payload and do something with it. You could use an interceptor to "reject" the response.
More information on transformResponse and "interceptors" in the $http documentation:
http://docs.angularjs.org/api/ng.$http
Related
Need to fetch the build values from apache.org. So i am using their api
https://builds.apache.org/api/json
I tried angularjs $http.jsonp but not able to fetch the data.
In chrome console under network json api is getting loaded but the data is not getting returned instead it is throwing the response as error.
app.controller("jsoncontroller",function($scope,$http){
var url='https://builds.apache.org/api/json';
$http.jsonp(url).success(function(data){
console.log('success');
})
.error(function () {
console.log('error')
});
});
Getting the error as
Uncaught SyntaxError: Unexpected token :
error
As per the jsonp angular docs, you must append JSON_CALLBACK to the URL: https://builds.apache.org/api/json?jsonp=JSON_CALLBACK
However, that URL doesn't work because even when the callback parameter is specified, the server still sends back a content-type of application/json, instead of the expected application/javascript. This causes it to be parsed (evidently) by the json parser instead of the javascript callback needed for JSONP to work. I'm not versed enough in JSONP or Angular to know who is it fault here.
I've made a fiddle with this working with another URL.
[Update]: The apache build server appears to use Jenkins, which has disable JSONP from the remote API. You can verify this yourself by trying to hit their jsonp endpoint, which returns a 403. You'll have to use another endpoint, no way I can see around this.
I have a webservice method that if I call directly via url GET returns XML without issue.
However, POST to that same url with Content-Type Json, it fails.
I think I can figure out the issue (I'm guessing it's an encoding or bad character somewhere in there) but I don't know how to debug the problem.
If I set a breakpoint in the webservice, it runs to completion. The failure appears to be happening AFTER the method returns, but BEFORE the json is returned to the caller.
How can I get in between to trace the error?
Please let me know if I can provide more context to help, but I really just need to know how to get in there.
EDIT:
The web service is configured to receive POST and return JSON and in fact DOES correctly return JSON in some cases. However, there are certain calls that are failing, so I need a way to trace this or debug it somehow and figure out why some calls are not working.
The web service is likely not configured to receive POST requests, especially if you are receiving a 405 Method Not Allowed response status.
Although I didn't find a way to debug or intercept the request to find the exact answer, it turns out the problem was the size of the content being returned by the webservice. Following this answer: ASP.NET WebMethod with jQuery json, is there a size limit?
and increasing the json limit fixed the issue!
Is there a way I could have trapped this to find the error without just guessing it was a size limit?
I've just implemented an FB.ui 'send' call. I process the returned value in the callback function and, not finding any documented reference, I wonder if I can investigate what's inside this 'response' JSON object. In PHP it is fine but I'm in JavaScript and I just want to process in the client, not additional server calls.
Right now I can just say that 'response' is 'null' or not. How can I find it's set of 'response.value' or some kind of de-serialization of the object in a string?
Thanks
Have you installed Firebug (if you use Firefox) or do you use Chrome? I believe if you call console.log with your object, it will allow you to inspect its structure in the Firebug Console Log. In Chrome, it will be logged in its Console Log.
Here is a good tutorial with more detail on using console.log.
New here. I've searched quite a bit for a working solution to my problem, but even though I have found posts with promising titles, none of the solutions have worked.
I am deploying an MVC2 web app to a client's server.
I did my development on Win2k8 Server, but they are running Win2k3 sever.
The app's only purpose is to receive some record ID information as HTTP parameters, check in the database for the status of the given record or records, and then return the status information as a simple string such as "Completed" or "Incomplete" in JSON format.
This getJSON code works fine in the development environment.
Inexplicably to me, on the client's server, the getJSON request receives a null response from the application.
There is no cross-domain action AFAIK... the result is the same from the client's server or from my machine via VPN.
In the MVC model's Json code, a common solution for people is to add the "JsonRequestBehavior.AllowGet" attribute to the Json result being returned. I did this long before trying to deploy it, and as I said, it has worked fine in the dev environment.
Using Firebug, I have watched the same request URL get sent to both my local server and the client server - the response headers from both servers are the same, but the response content from my server is shown as:
{"Result":"No Data"}
Which is what I want.
There is literally no content shown in the response from the client's server..? But the request gets an HTTP 200 code and is recorded as a success in the reponse's status attribute.
The response header content type in both situations is "application/json"
But wait, there is more!
If I manually enter the request to each server in the Firefox nav bar, and hit enter, in both cases it responds with:
{"Result":"No Data"}
Which is what I want. So why can I get the result I want from the MVC app on the client's server only when I hand-enter the request URL in Firefox, but not from the Javascript code?
I have tried forcing different output content types ... using the jQuery ajaxSetup method...
$.ajaxSetup({
async: false,
dataType: 'text'
});
or
$.ajaxSetup({
async: false,
dataType: 'html'
});
and again wtih 'script', and 'json'. I also tried the conversion options such as 'text json' or 'html json' or 'json text' and so forth.
Some of the posts I'm reading, and my gut feeling, though, suggest the problem is not the jQuery code making the request that is at fault... I don't see how the same jQuery request point to a different server running the same app would suddenly cause that server to send back a 'null' value.
By null, I want to be clear... I mean nothing is sent. There is no {} or {null} or any sign of JSON... just blank whiteness of non-existence :P
Even if nobody knows the answer, I would love some input perhaps suggesting where I should focus my sleuthing ... client or server?
If the problem is the server, it seems hard to really know that the MVC stuff is running 100% on the IIS6 server, but in general it seems to work. I have a different MVC app running on the client server which responds to the virtual paths, and generally runs the same as on dev machine.
I have found one thing ... the request headers are somewhat different? The Request Headers sent to the IIS7 setup include an "X-Requested-With: XMLHttpRequest", "referrer" , and "cookie" field/value.
I could guess that the lack of the "X-requested-with: XMLHttpRequest" in the IIS6 request headers is a clue, but I do not see then how the same javascript code pointing at a different server can generate different request headers itself. So how else are those being generated?
The javascript is embedded in an ASP.NET page, btw.
Oooh.. frustration!
Thanks for any input.
Odd Progress ... apparently there is some sort of issue with IIS6 handling the query. Although I have not payed any attention to JSONP, a post elsewhere suggested that sometimes use the "&callback=?" parameter at the end of a .getJSON request URL would force it into GET mode and that worked frequently for problems getting data from the server. So I did that... and it did work, sort of. The proper {"Result":"No Data"} was returned in response to the request... which seems good. However, the way that the JSONP callback works, it generates its own script to do the calling and fetching and interpreting of the incoming JSON. In this case, it interprets the JSON to need a label which it does not have, thus an error is thrown "invalid label" ... there must be some way to hack things to just deliver the JSON, but the whole required use of JSONP callbacks suggests that the server configuration is wrong, right? Or why does it work without JSONP for IIS7 and not IIS6?
Despite my not liking the callback JSONP solution, it appears to work ok. The error is still returned about an invalid label, but that does not appear to stop the remaining javascript from running... and so the application is working with IIS6 now. I have not tested the fix of using the callbacks and JSONP against IIS7 yet, but I expect it will work well enough.
Here is a link to the discussion that lead me to my current solution. I do still hope to find a more elegant solution, however.
NeoWin.net
Are you certain that your App Extension Mappings are set up correct?
Follow this article for running MVC2 on IIS6 and ensure all the different configurations have been done, that's probably the first step before going further and investigating specifics.
I'm really inclined to believe it's related to HTTP Verbs.
Not a great title but I'm looking more for some guidance, have searched quite a bit. I'm building a web app with an MVC framework (but I think this is a more generic question). I'm trying to make many views that do a lot of AJAX style calls and say I have a site with users and they can add folders and files to their profile page. So the URL maybe like:
/profile/{id}
I have a Profile controller that returns a view with various information. I'd like files and folders listed on the profile to be dynamic so I want to populate it through AJAX calls. I was thinking I would have a URL like
/listFolders/{userId}
and
/listFiles/{folderId}
Is it reasonable to have these URLs return a JSON object for these two URLs and not even provide an HTML view (since, for the browser, the view will just be the whole profile page)? Also, what should I return for errors, say if the user/folder doesn't exist or the current logged in user doesn't have access the data? Is it reasonable to just set 404 or 403 HTTP error codes or do they need to return some kind of HTML? What if there are multiple reasons for it to fail and I'd like to pass that along? Should I arbitrarily choose HTTP error codes or define integer return codes like 0, 1, 2, etc? Also, should the URL specify that they are JSON, like listFoldersJSON instead of listFolders?
I have used JSON in my previous projects. For errors, we return error codes.
We decided to do so because we were dealing with API clients. So we want to deal with error codes (REST is based on HTTP, so it was appropriate to return error codes).
Since you are writing your own application, you can pretty much choose how you want to send your errors to the view. You can create a error json object and in the view you have to check whether this object is not null.
pretty much a if-else in the view. Else you can return error codes and check for the code before rendering the JSON into whatever view you want to.
I would go with error codes, because that complies with the REST philosophy.
Generally speaking, I handle this situation by throwing a 500 internal server error with a status message. Most client libraries such as jQuery provide built in error handling with a failure callback like:
jQuery.ajax({
success:function(response){
//do some success stuff
},
error:function (xhr, ajaxOptions, thrownError){
//handle error
alert(xhr.responseText);
}
});
It's entirely feasible to return JSON objects as opposed to actual views.
As far as the url, you can use listFolders and listFiles without taking on the JSON. However, I recommend you use lower case urls for the sake of how the server is setup. For instance, I know on Apache that sometimes listFiles would be fine, but listfiles would lead to missing page exception.
With regards to errors: You could setup a header of sorts in your JSON response and use whatever system you'd like. For instance, you could do something like
status_code: 0 //where 0 means successful
status_detail:success!
Where, if the status_code is something other than 0, you'd check the status_detail and know to ignore everything else inside the response.
Also, what should I return for errors, say if the user/folder doesn't exist or the current logged in user doesn't have access the data?
These are basic HTTP Error codes:
401 : Unauthorized
404 : Not found
There's a whole slew of error messages in the HTTP spec:
HTTP Status Code Definitions
Also, should the URL specify that they are JSON, like listFoldersJSON instead of listFolders?
Generally, a good way to handle this is for the client to set the 'accepts' header to something like 'text/json' or 'text/xml' and for the server to parse it out and respond with the correct response. This way you can use the same URL but send back different views of the data (if you ever wanted)